3com MSR 20-20 참조 매뉴얼

<Sysname> system-view

[Sysname] voice-setup

[Sysname-voice] subscriber-line 1/0

[Sysname-voice-line1/0] transmit gain -6.7 

VoIP entity view

None

Use the tunnel-on command to enable tunnel function.

Use the undo tunnel-on command to disable tunnel function.

By default, the tunnel function is disabled.

Tunnel function can assist in negotiating process of such nonstandard H.245 
message as transmitting DTMF digit transparently.

Only after successfully enabling H.323 fast connection mode, can you fulfill the 
configuration of tunnel function. Being the calling gateway, it can be decided 
whether or not to enable the tunnel function for each call on the router. Being the 
called gateway, it shall be decided whether or not to enable the tunnel function 
based on the status of the calling gateway. That is, if the function is enabled on 
calling gateway, it will also be enabled on the called gateway. Otherwise, tunnel 
function is disabled on both sides. To implement this function, you need to carry 
out the voip called-tunnel enable command to enable the fast connection 
function on the terminating gateway.

During actual configuration, it is only necessary to fulfill this command for the VoIP 
voice entity at the calling gateway.

fast-connect, outband, voip called-tunnel enable and voip called-start.

# Enable the tunnel function for VoIP voice entity 10.

<Sysname> system-view

[Sysname] voice-setup

[Sysname-voice] dial-program

[Sysname-voice-dial] entity 10 voip

[Sysname-voice-dial-entity10] fast-connect

[Sysname-voice-dial-entity10] tunnel-on 

type { 1 | 2 | 3 | 5 }